How are alcoholic liver disease and viral hepatitis different?

Different causes: One is caused by alcohol and the other is caused by a virus which infects the liver, hepatitis b and c are the most common causes of chronic viral hepatitis. As both of these affect and damage the liver they may have similar symptoms such a jaundice and evenually cirrhosis. The treatment however would be different. Having a viral hepatitis and drinking would speed the progression of the damage.

Patterns of injury: Acute viral hepatitis presents with transaminases (lft's) in the thousands with alt>ast. Acute alcoholic injury to the liver causes ast>alt and the levels are <500. Importantly, the mortality of acute alcoholic hepatitis is much higher than viral hepatitis. Chronic liver injury is another story.